How to build a transportable motorized bike?

[Ferro]

Hi, I just registered here because I see that there are plenty of experience with little motors to apply on a bike. First of all excuse me for my english, i'm from italy and it's not my language.

Me and my gf would like to travel accross the Black Sea next year with foldable bikes, which fit well in a large backpack. We're thinking about motorizing those bikes.

We have to do some 2000-3000km so we need reliable motors, but I don't know much about this and that's why I ask you.
I thought about a chainsaw 50cc motor, simple to mount on the rear tyre, and transportable as well. Do you think it will last for 3000km?
We're goin to stay on the bike for 4-5 or maybe 6 hours a day, I don't know if this type of engine can afford this long operational time.
A classic 50cc bycicle oriented engine how long will last?
We're just planning next summer holidays, so if it's not worth we'll go by motorbike but the idea of taking the airplane and then have a motorized bike there is more fascinating me

I also saw the Revopower kit, anyone has tested it?

 

[deacon]

I have just started to work on chainsaws for bikes so I can't tell you much about the longevity. I am working with a 33cc chainsaw at the moment and have a 42 on the way now. I have no idea what a folding bike will do with one and never even heard of the kit.

What is the lay of the land there. Is it flat or hilly and how fast do you want to travel.

 

[Ferro]

we are planning to go to flat land, it's on a lake so there are many beaches and plains.

do you know any very light engine that can burst you to 30-35 mph?
i saw on ebay some chinese 80cc engine but it says that it goes no more than 20mph

revopower is a kit that will fit in the front wheel and it's very compact

 

[deacon]

Im the wrong man to ask to be honest. My bikes are designed to run about twenty or so. I frankly do not feel safe on a bicycle going thirty miles an hour. I have had my china kit up to 28 but was way to unstable for my taste. Possibly if you have big tires on it and the bike itself has a heavy frame it would feel stable enough but I am not sure about that. Some of the others here are more into speed.

If the ground is flat, you won't really need that much engine frankly. Since bicycled travel the world under people power, I would think the traffic passing you in Europe wouldn't be all that scary.

Why not take a train there and rent a couple of scooters? That would seem to be the best thing for the power you seem to want. I'm sure you could rent a scooter for the price of building a bike that would do what you need.

 

[Ferro]

you must return the scooter in the place where you rented, and if you do 2000km it's a little impossible to do, especially if you rent a scooter in Bulgary and you end your journey in Ukraine or Russia.

we're looking for something that we can bear in our backpack, i'm something 200lb and the bike is 20lb, i tried about 25mph and i feel comfortable with that.

i'm searching for some engines on ebay but here in europe there's no such things, thanks to all the epa laws that we have (one of the most restricted of the world).
in east europe i think we can go without license, here in italy and the rest of west eu you would have needed a license for the motorbicycle.

 

[deacon]

The best thing I can think of is to ask around where they are more familiar with what is available there and what the restrictions are. Frankly over here I would say get a 25 to 31cc weed whacker and build a frame for the front wheel. That would be the easiest thing to do. But I don't have any idea about what is available or what the laws are there.

I believe that a 31cc two stroke engine running friction drive wide open on a flat stretch could reach 25 and maintain it, but I have no proof of that. I am pretty sure my 33cc chainsaw will do that. I live in an area full of small hills so I have never found a purely flat area to let mine out. A friction drive has to build to full speed. In other words it accelerates then it just keeps on slowly going up. By the time that happens here I am on another incline so I have no idea exactly what it will do.

I weight 210 lbs so the weight issue is about the same for us. You should go to the store and hold a 50cc chainsaw to see what the weight is. My 33cc is pretty heavy compared to the weed whacker. If they have weed whackers there it would be the way to go on the weight issue anyway. I wish I knew more about what is available there.

Do they have leaf blowers there... Those engines in the states are about the same as week eaters... Also the hedge trimmers have gasoline motors here sometimes.

 

[5-7HEAVEN]

I installed a Staton friction kit w/Subaru 1.6hp engine and 1.125" roller on my 20" Dahon. I weighed 190 lbs(about 87kg), and this engine was a good match. It was quiet, cheap on gas, no oil mixing, and top speed was about 27mph. However, the bike would no longer fold. Then I changed to Staton chain drive and Mitsubishi 2.2hp engine. The bike would now fold, but it would not fit into the bag.

If I were to travel like you, I would remove the engine kits from the bikes every time I needed to travel by train. It is very quick and easy to remove and reinstall the complete engine kit in less than 20 minutes.You may have problems trying to transport gasoline engines on airplanes, maybe even trains.

Use a 4-stroke Honda or Subaru engine, which can go for longer distance than 2-stroke. You might get 200 mpg(80km per liter) of petrol.

Install a large seat, because it will a bumpy ride with no front or sear suspension. Don't plan to go faster than 30mph(48 km/hr) in spurts, for safety reasons.

Good luck.

 

[comfortableshoes]

I'm not sure i"d want to go more than 25 mph on a folding bike... I had one I considered motorizing but... It seemed dangerous.

The Dahons though are a good quality folder. With the folding involved I'd do a front wheel install instead of a rear wheel- shorter amount of cable to tangle or break.

Considering the European EPA laws I'd got with a 4stroke kit as well, that's not even considering the longevity of the engine. The 4strokes will go longer and harder for a long period of time.

You might be able to figure out a way that you can get it folded if you do the design right...

Good luck on this, read the forum there's a ton of info on here to help you with your build.

Also take lots of pictures so that you can load them up so we all can see your adventure!!!

 

[deacon]

I was glad to see someone else answer this member since I have never even seen a folding bike.

 

[Ferro]

I have to thank you all for the replies

We have 2 Dahon model FLO, the mountain bike from Dahon, it fits quite well my huge backpack. We had a lot of luck buying them used from a shop failure auction, because we could not afford the price of new (too expensive bikes).
I think the best thing to do is like 5-7HEAVEN said, to remove the engine each time we take the train is the best thing, the fact is that we will travel a lot with train with bikes in the backpack, there is no problem at all with it.

The final aim to all this is to take the transiberian train next years and go biking on the Bajkal lake in Russia, but this is too far for now... It will be enought if we will have our bikes up & running for a tour of north italy in winter and next summer for the black sea, if we see that this project (bike+engine in backpack) it's affordable and most of all, feasible.
We have been in denmark, uk and france, but without the engine, only bike

I'll start searching for some 4stroke engine, I also thought that a 4s is better than 2s for long distances, but I didn't know many things about it. In east EU there are no laws about 2stroke engines, so i can go with it as i want.
I read a lot on this forum, it's helping me so much figuring out the feasiblity of the project.
I go search for more info and see if here there are some reseller of those 4str engines... it's quite hard to find one i guess
thanks for now!

 

[datz510]

When you do make the trip, make sure and post up photos of your journey! Sounds like a lot of fun!

 

[Large Filipino]

This backpack thing is freaking me out. Do you intend to CARRY your bike?
Why not roll it along with you? Does it have to be stored? And how about the fact that your bringing inside a gas engine?

 

[deacon]

I'm a little surprised that you couldn't just take the bike on with you somehow. Something like the regional bus service here with the bike rack on the front. I thought Europeans were big bike tour people.

 

[comfortableshoes]

This backpack thing is freaking me out. Do you intend to CARRY your bike?
Why not roll it along with you? Does it have to be stored? And how about the fact that your bringing inside a gas engine?

The little fold up bikes are quite light weight- 18 pounds or so, They have smaller 20 inch tires and fold up quite compact- You can easily strap it to the back of a large framed back pack. I'd assume that the Dahon's are even lighter than the cheapo one I had, which had 12 or 16 inch tires and was good in a pinch, but I wouldn't have wanted to have spent more than a half hour or two in that saddle...

The gas engine thing I question as well. I suppose there is some sprt of carry on travel on the larger Euro trains that we don't have here. I know you'd never be able to bring anything even remotely like a goped onto the train system here. Are there special storage cars? And shoot what do you do if they loose that one very important piece of luggage- or is that an American only thing- getting your luggage lost?

 

[Large Filipino]

I say if you can get it in luggage and ensure your gas would in no way leak then maybe you can get away with it.
You may need to consider electric here just for that reason.

 

[eDJ]

I've already responded partly to this in Ferro introduction post. But a 2K to 3K Km trip would roughly translate to 12 to 18 hundred miles. I tend to favor the electric bike design if for a folding bike. I would see it as a 5 or 10 speed pedal drive with the simple electric front hub drive motor and a 50x100x400
mm battery pack with built in recharger. The lighter in weight the better.

I've done some hiking and back packing as a kid in boy scouts hiking on the Rocky Mountains trails with a 50 lb pack (25 Kg). Many of the less solid guys couldn't make it thru the whole expedition while carrying 25 lb packs (12 Kg).
We used aluminum pack frames to mount our packs on so we could carry the greater wieght more efficiently while we hiked 10 to 18 miles each day. (16 to 28 Km). As a 17 year old kid I said, "that's enough of this" when the expedition was finished.

If you are bike-hiking and have decent roads to travel, access to restaruant food, and good bedding to sleep on you'll be able to endure a longer trip. Add to that the motorized bike to ride then it won't be so stressful. I'd spend some money on a very comfortable seat for the bike and perhaps a lambs wool cover for that seat.

I don't know how much time can be set aside for Ferro to make the journey and how much journey can be endured for them. I would suggest
planning the whole trip and dividing it into segments. Having several segments to plan for in different seasons may add to the enjoyment of seeing the world around you during plesant weather. My experience with a "long" trip in boy scouts that was a hurry, hurry, do this do that from the time we left home till the time we got home left me with a preferance for several shorter trips in each year. I realized the meaning of the saying that....."the two best days of a vacation are the day you start out and the day you return home".

My concern here is for the balance of endurance over logistics. 5 to 6 hours a day riding a bike day after day is physically demanding. A folding bikes suspension will likely be in it's seat. 40 to 55K's per hour may sound like fun but over 2 to 3 thousand Kilometers could transform the vision of a vacation to see the world into an grueling endurance race like the Mille Miglia. I'm thinking a female partner along on such a trip would have to have to be a strong girl. Perhaps the journey could be taken in segments where you are dropped off and picked up at the beginning and end and then transported back home ? This may be the more plesant way.

 

[5-7HEAVEN]

If you have 26" folder bikes, they're much safer, softer riding and better handling than 20" Dahons. I gave my 20" Dahon away because I know I'd hurt myself badly if I kept it motorized.

The 4-stroke engine with 96-ounce remote tank is a great long-distance runner. Combined with 23-ounce stock tank, you might get 400 km per fillup. You can shop around for the best gas prices along the way, instead of having to pay a high price with short-range fuel tanks.

This seems like a very practical way of traveling, especially since you already used these same bikes on long-distance pedalling. It is good that both bikes are identical. Install the same engines on them for simplicity. Use smooth tires with kevlar protection, front and rear.

I'm excited for you; good luck on your trip!

 

[LordMaximo]

I am surprised you have not investigated the possibilities of taking a regular, full sized mountain bike on the train. Most trains have compartment cars with bike hangers in the cargo holds. I use to travel cross country here in the USA on trains, and we had zero problems with bike hangers. And, you can also get a leak proof, heavy duty stowage bag for your engines, this will help keep the fumes to a minimum. And last but least, I would go with a 4-stroke engine, 5-hp min, and tie it into the gearing system of your mountain bike. It is quite common to add a small 5-hp engine and making good usage of your rear gears. You can bet on 500 to 600 km per tank full.
And, if you need to dispose of the fuel before loading, I am sure you could find a local petrol station who would buy your unused fuel.
It would help also to find the petrol stations on your route, and inquire if they would allow for such a transition. I am adding a 196cc 4-stroke engine to my mountain bike in a couple weeks. Plus I am locating a 15 Ltr cylinder tank for the center cross bar, like the old track racers use to have on their designs. Good luck on your trip and building your rides.

Maximo

 

[5-7HEAVEN]

Lord, why would you need a minimum of 5hp and why would you tie it into the shifting system? The Subaru 1.6 hp engine weighs 8 lbs. How heavy is a Honda GC160 5 hp engine? Maybe 33 lbs.? Wouldn't you want to maintain the smallest, lightest, simplest motor system possible on a flatland trip, especially if you'll be removing/reinstalling the engines?

Lord, it is not common to install what you recommend. There are no commercial kits available that offer 5 hp+ engines, especially running through the bike's shifting system.

How big is the fuel tank to allow 375 mile(600km) range for a 5 hp+ engine? Seven gallons if you get 53 mpg? How much would a full tank weigh? Maybe 56 lbs including the tank? The 96 oz plastic tank full of gas might weigh 7 lbs. The entire friction drive assembly with big tankful might add 23 pounds to the 37 lb. bike. Lord's recommendation might add 95 lbs.

Remember, they're backpacking their bikes.

Lord, please post pictures of your monster engine/bike when you're done, especially the 15 liter(5-gallon) tank in the center bar.

 

[Ferro]

the reason why we don't take regular bikes is that often here small and mountain trains do not have place for bikes.
try to look at the train we took in Corse (France):

trinighellu - Google Ricerca immagini

@ LordMaximo: too heavy, I already own a 1978 Honda CX500 if I want all that weight, but it's not a bicycle
i'll post more later, i'm still reading the replies